Why does my air conditioner make gurgling sound?

Hearing a splashing or water sound isn’t uncommon, whether it be from your toilet, hose or bath. However, if this sound is coming from your air conditioner, this unexpected sound may cause concern. 

Although there are a number of reasons that could cause your air conditioner to have a water sound, none of them should be ignored. 

Condensation

The way that an air conditioner works is by taking the humid air and getting rid of it. This means that a well-functioning air conditioner creates condensation. However, once the water is taken out of the air it needs somewhere to go.

For this reason, air-conditioning units have drain pipes as part of the unit. This is where the first type of water sound can be heard. If you hear a dripping sound coming from your air conditioner it will usually be the condensation dripping into what’s called a drip pan.

Then from the drip pan it usually goes to the drain pipe, and then ends up over a gully, in a downpipe of another type of water drain. If this sound is becoming irritating then the simple solution is to empty the drip pan completely and the sound should stop. 

Clogged drain pipe

As the air conditioner cools the air, it produces condensate (water), which is typically drained away through a small drain pipe. This line can become clogged with debris, such as dirt and dust, causing the water to back up and create a water sound. To fix this problem, you can try cleaning the drain line to remove any blockages. This can be done by using a pipe cleaner or pouring a mixture of vinegar and hot water down the drain pipe. If this doesn’t work, it may be necessary to call a professional to clean the drain. If you find that you have a clogged drain line, you can also check out our article here to get more information on what to do.

Water running or splashing

Another water sound that may be heard from an air conditioner is the sound of water running or splashing. If this is the case then you may have a bigger problem on your hands. Since your air conditioner is designed to evaporate humidity in the room there is no water build-up as such in the unit. If you are hearing a splashing or running water sound, it is likely that the excess condensation is not draining. This can then lead to a larger issue and could cause leakage in your home. So if this is the case proceed with the following steps to make sure no further damage is done to your home and air conditioning system.

1. You must first turn the AC unit off 
2. Check the drip pan to see if it is overflowing, if so, empty it 
3. Check the condensate drain. If the drip pan was overflowing, make sure you also clean the condensate drain (the line where the water drains through) as it will likely be clogged 
4. At the same time, clean your indoor and outdoor filters since dirty air filters block airflow including to to the evaporator coil
5. A suitable qualified person should also also check the refrigerant levels since low refrigerant can cause the coils to freeze up causing excess water when they thaw

These are just some basic steps to fix a hopefully simple problem, however, sometimes it is best to contact a professional and get your unit examined properly. Ignoring a gurgling sound in air conditioning and many other life situations is not a good idea. 

Dirty air filter

Another common cause of a water sound in an air conditioner is a dirty air filter. A dirty filter can restrict airflow, causing the evaporator coil to freeze up and produce excess condensation. This can lead to a water sound as the excess water drips into the drain pan.

To check the air filter, open the filter housing and remove the filter. If the filter is dirty, most modern filters can be washed and dried before being inserted again. The filter is located in the indoor unit when it comes to split systems. In the case of ducted units, there is a filter near the inlet opening, usually located in the ceiling. Be careful when you open such units as sometimes they have accumulated a lot of dust and can make a real mess when opened.

Frozen evaporator coils

If the air filter is clean and the condensate drain is clear, the problem may be with the evaporator coil. Over time, the evaporator coil can become dirty or damaged, which can cause it to freeze up and produce excess condensation.

The evaporator coils in an air conditioner are responsible for cooling the air. If these coils become frozen, the water that forms on the coils as the air is cooled may leak and cause a water sound. To fix this problem, you or a professional will need to thaw the coils and make sure they are clean.

To check the evaporator coil, turn off the power to the AC unit and remove the access panel. Look for any signs of dirt or damage on the coil. If the coil is dirty, you can clean it using a soft brush or a special coil cleaner. If the coil is damaged, it may need to be replaced. Also, is your air conditioner properly sized and installed?

What about the blower wheel?

Another possible cause of a water sound in an air conditioner is a damaged or dirty blower wheel. The blower wheel is responsible for circulating air through the outdoor AC unit, and if it is dirty or damaged, it can cause the evaporator coil to freeze up and produce excess condensation.

To inspect the blower wheel, turn off the power to the AC unit and remove the access panel. Look for any signs of dirt or damage on the wheel. If the wheel is dirty, you can clean it. If the wheel is damaged, it may need to be replaced.

While water sounds in your air conditioner can be alarming, in most cases it is not something that will cause the unit to stop immediately. It’s more of a symptom, that maybe a maintenance check is overdue, or that you are facing very humid conditions. 

The only time a water sound should be alarming is when you can see leakage coming from your air conditioner in a decent volume or when the sound is a very loud splashing or running sound, otherwise, a slight water sound is actually fairly common in air conditioners. So it’s all a matter of degree.